What's the orientation for the up camera supposed to be

[thereza]

It's not obvious, I suppose - could be rotated 180deg.

If I move the gantry left/right/up/down, the needle moves left/right/up/down - is that right?

odd thing is that when you are plotting things overlaid on the downcamera image, the y axis is filliped, and when you plot over the upcamera, the x axis is flipped. i'm a bit confused...

[JuKu]

> If I move the gantry left/right/up/down, the needle moves left/right/up/down - is that right?

Yes. This makes most sense for the user.

When you plot over or make measurements from the image, there are several coordinates confusing things. The geometry (one camera is looking down, one up), the coordinates of the plotting system have y zero on top, machine has it on bottom. Just flip coordinates as needed.

[thereza]

Do these make sense (are correct?)

DownCamera :
machineToPixels: flip Y, apply scaling and zoom.
pixelsToMachine: flip Y, apply Scaling and zoom

UpCamera:
machineToPixels: flip X, apply scaling and zoom
pixelsToMacheine: flip X, apply scaling and zoom

[mrandt]

I checked my camera and - while looking at the picture in LitePlacer software - the orientation matches Juha's description. Left move of machine shows as needle moving left in cam picture, forward move of machine shows as needle moving up in cam picture.

I guess it is important to note that the picture is flipped horizontally (mirror X) in LitePlacer software.

So when opening the webcam stream in VLC or other software, left and right will be swapped - i.e. left move of machine shows as needle moving right in cam picture.

Similarly, the down cam image is flipped vertically (mirror Y).

I think Reza's description is accurate. Flip Y for down, flip X for up camera.

Confused me at first...

[thereza]

what's more confusing is that the software flips the upcamera in the y axis but the camera is rotated and so the effect is flipping x? still not able to get my head around it.